|
Dip In Road
|
|
Source：Internet Author：Unknow Pubdate：2008-03-18
|
|
xroy (Civil/Environme)
5 Mar 08 0:49
hi,
does anybody know what a dip in road is? when is it best to use and what should be the specs.
i am designing an access way for the utility area of the project i'm working on and this particular access way will block all possible drainage going to the ditch around that area. our client wants to use a dip in road to solve the drainage problem of that area.
xroy
msquared48 (Structural)
5 Mar 08 0:59
"DIP" stands for Ductile Iron Pipe, which requires less cover under traffic load than either concrete, PVC or CMP pile.
Then again, a "dip" in the road is a depression, or a really stupid person standing there... Mike McCann
McCann Engineering
xroy (Civil/Environme)
5 Mar 08 1:40
hi msquared48, 字串3
actually, Ductile Iron Pipe was the first thing that came in to my mind. But according to our client, it's not.
I agree that it's a road depression. I just wanted to know
what are the specifications for this type of design. A drawing detail would be the best answer.
thanks
chris
PELS (Civil/Environme)
5 Mar 08 12:05
From your very brief description of the circumstances, it sounds like you would be better off using a culvert in the roadway rather than a "dip" or depression. The culvert allows the drainage to flow through the roadway without having a low area. If this is a low traffic volume access road, there are very economical pipe types such as CMP or HDPE that can be used for the culvert.
sam74 (Civil/Environme)
5 Mar 08 12:42
If it is a public road then you would want to look at K values for the vertical curve. Minimum design K values can be assigned for vertical curves in the roadway which have variables involving design speed, algebraic difference in grades, and length of vertical curve. See the link for a chart for sag curves and google vertical curves and K values to find more info. 字串2
http://www.nj.gov/transportation/eng/documents/RDME/figure4j.shtm
francesca (Civil/Environme)
5 Mar 08 12:43
The design of a structure to convey storm water is dependent upon the volume of storm water to be conveyed. This is true if it's a culvert or a "dip."
Even if this road is a temporary structure for during utility construction it needs to withstand at least a 2 year design storm, possibly a 10 year design storm. If the road will not be surfaced, then a "dip" or traversable ditch (ford) would need to be armored with riprap, concrete or asphalt, all of which would likely cost more than a culvert.
xroy (Civil/Environme)
5 Mar 08 18:26
Actually, the original design was to use a culvert but our client wants to use the dip instead.
Tnx for the advice. 字串4
RWF7437 (Civil/Environme)
5 Mar 08 18:32
Dips are widely used in the desert southwest of the U.S.
Try searching for standard drawings in the DOT websites for Arizona, New Mexico and possibly California and West Texas.
good luck
PELS (Civil/Environme)
5 Mar 08 21:04
I must confess I have not heard of this "dip" concept. Apparently it is used quite frequently in the design of forest roadways. There is some minimal design criteria and graphics in here:
http://ttap.colostate.edu/Library/MISC/USDA%20077%201803-SDTDC.pdf
xroy (Civil/Environme)
5 Mar 08 21:34
Hi Pels,
Thanks for posting the link. It's really is very helpful. 字串2
Chris
cvg (Civil/Environme)
9 Mar 08 17:15
here is the phoenix detail for dip crossing
- http://files.engineering.com/getfile.aspx?folder=4956a4e3-869d-46c1-af1e-fe
rconner (Civil/Environme)
10 Mar 08 11:18
I was just curious --is an effective "shoulder" transition maintained with these things?
ptmoss (Civil/Environme)
15 Mar 08 10:52
A dip in the road is simply that. Come down about 5" or so about 8-10' in off the edge of your main road. Then your utility road heads uphill. Obviously this wouldn't be needed if the utility road drops away from the main road.
If there is a ditch along the main road then you'll likely have problems matching the depth of the dip to the bottom of the ditch. I have property owners ask to do this all the time on their driveways when they're too cheap to put in a culvert. 字串4
The only time I relent is when the driveway, or in your case the utility road, is at the crest of a hill along the road. In this case the water from the driveway ditches will flow off in opposite directions downhill and the dip will divert water that might come down the driveway so it doesn't flow out into the main road.
If the utility road does not come off a crest like this and there is a ditch to cross then you need to design a culvert.
（Click：）
|
| Previous：Footing Excavation Testing Next：1 |
|
[ Add TO Favorites]
[TOP] [PRINT]
[CLOCE WINDOWS] |
|
|
|
